This invention relates to a radiometer probe which is adapted to be attached to a non-contact temperature-measuring radiometer for providing such a radiometer with a contact temperature-measuring capability.
Portable, or hand-held, radiometers have been used extensively to conveniently measure temperatures of various objects without physical contact. Temperature measures of the contact type suffer the disadvantage of disturbing the temperature of the object into which it comes in contact. However, non-contact temperature-measuring radiometers have a difficult time of measuring temperatures of objects or specimens in which the emissivity is unknown, and especially where the specimen does not have a high emissivity. Emissivity may be defined as the ratio of the radiation emitted by an object to the radiation which would be emitted by a "black body" at the same temperature. When the emissivity is unknown, and particularly when it is small, the infrared radiation emitted by the object or specimen being measured bears little relation to the actual temperature of the specimen or object. Accordingly, the radiometric sensed temperature may be in large error. If the emissivity is known, the instrument may be calibrated with respect to such emissivity to provide accurate measurements.